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27 entries match these filters
- 0414 HTTP headers you should set on every site The response headers that make a site safer and faster: HSTS, Content-Security-Policy, X-Content-Type-Options, frame protection, Referrer-Policy, Permissions-Policy and Cache-Control, with Nginx and… Intermediate · Cheat sheet · Any system Article Making requests · Web servers & reverse proxies 15 Oct 2026
- 0421 grep, sed, awk and jq: the four text tools you will use every week A working reference for the four commands that handle most text on the command line: grep finds lines, sed edits them, awk… Intermediate · Cheat sheet · Linux, macOS Article jq & JSON on the command line · Modern command-line tools · Text processing 15 Oct 2026
- 0380 GitHub Actions cheat sheet: triggers, matrix, secrets, caching The GitHub Actions syntax you reach for most, in copy-ready blocks: event triggers and filters, build matrices, secrets and permissions, dependency caching… Intermediate · Cheat sheet · Any system Article GitHub Actions 15 Oct 2026
- 0397 PowerShell cheat sheet The PowerShell cmdlets and patterns you use every day: files, text, processes, services, filtering, exporting, remoting and the operators that trip up… Beginner · Cheat sheet · Linux, macOS, Windows Article PowerShell 15 Oct 2026
- 0346 The SSH config file: aliases, jump hosts and keys per server Reference for ~/.ssh/config: short names for servers, the right user, port and key per host, ProxyJump through a bastion, connection reuse and… Intermediate · Cheat sheet · Linux, macOS, Windows Article Keys & config · SSH 15 Oct 2026
- 0329 Docker CLI cheat sheet The Docker commands you reach for every day, grouped by what they act on: containers, images, volumes, networks, logs and cleanup, with… Beginner · Cheat sheet · Linux, macOS, Windows Article Docker basics 15 Oct 2026
- 0232 mongosh cheat sheet: CRUD, indexes and explain() The mongosh commands you use every day: switching databases, inserting, querying, updating and deleting documents, creating indexes and checking a query plan… Beginner · Cheat sheet · Any system Article Basics 15 Oct 2026
- 0236 Redis data types and commands: a quick reference Redis stores values under keys, and each value has a type: string, hash, list, set, sorted set or stream. The essential commands… Beginner · Cheat sheet · Any system Article Basics 15 Oct 2026
- 0215 mysql command-line client cheat sheet The connection options, built-in commands and everyday SQL you need in the mysql (and mariadb) command-line client, on one page. Beginner · Cheat sheet · Any system Article Administration · Queries 15 Oct 2026
- 0222 Connecting to Oracle: SQL*Plus, SQLcl, EZConnect, tnsnames.ora and the listener Clients reach an Oracle database through the listener, using an Easy Connect string or a tnsnames.ora alias. Here are the formats, the… Intermediate · Cheat sheet · Linux, macOS, Windows Article Administration · Concepts & tools 15 Oct 2026
- 0185 Ansible ad-hoc commands cheat sheet One-line ansible commands for quick jobs across many servers: ping hosts, run a command, copy files, manage packages, users and services, gather… Intermediate · Cheat sheet · Linux, macOS Article Ansible 15 Oct 2026
- 0193 Linux logs reference: journalctl, journald storage, logrotate and centralized logging Read and filter systemd journal logs, keep their disk use in check, rotate classic log files with logrotate, and understand when to… Intermediate · Cheat sheet · Linux Article Linux administration · Logs 15 Oct 2026
- 0199 psql meta-commands cheat sheet The backslash commands you use every day in psql: connecting, listing databases, tables and roles, describing objects, timing queries, expanded output and… Beginner · Cheat sheet · Any system Article Install & connect · Roles & administration 15 Oct 2026
- 0174 Network and DNS troubleshooting commands: ip, ss, dig, resolvectl A layer-by-layer cheat sheet for "the server cannot reach X": interfaces and routes with ip, listening ports with ss, and name resolution… Beginner · Cheat sheet · Linux Article Networking & firewalls 15 Oct 2026
- 0176 apt vs dnf: package commands and automatic security updates The everyday package commands on Debian/Ubuntu (apt) and RHEL/Rocky/Alma (dnf) side by side, plus how to turn on automatic security updates on… Beginner · Cheat sheet · Linux Article Packages & updates 15 Oct 2026
- 0140 kubectl cheat sheet: the commands you use every day A compact reference of everyday kubectl commands: contexts and namespaces, listing and inspecting objects, logs and exec, applying changes, rollouts, scaling and… Beginner · Cheat sheet · Any system Article Concepts · Troubleshooting 15 Oct 2026
- 0157 oc cheat sheet: everyday OpenShift CLI commands The oc commands you use every day, grouped by task: login and projects, apps and builds, routes, config, debugging, permissions and admin… Intermediate · Cheat sheet · Any system Article Deploying applications · Troubleshooting 15 Oct 2026
- 0107 Proxmox VE command line cheat sheet: qm, pct, pvecm, pvesm and more The Proxmox VE commands you use most: qm for VMs, pct for containers, pvesm for storage, pvecm for the cluster, vzdump for… Intermediate · Cheat sheet · Linux Article Clusters & high availability · VMs & containers 15 Oct 2026
- 0121 PCA 3.x Service CLI basics: connecting and finding your way around The Service CLI administers the Private Cloud Appliance 3.x Service Enclave. Connect with SSH on port 30006 and use list, show, help,… Intermediate · Cheat sheet · Any system Article Administration & monitoring 15 Oct 2026
- 0124 virsh cheat sheet: everyday libvirt commands A quick reference for virsh: list, start, stop and inspect VMs, change CPUs and memory, manage networks, storage pools and snapshots, with… Intermediate · Cheat sheet · Linux Article Basics 15 Oct 2026
- 0082 HTTP status codes: the common ones and what to do A quick reference to the HTTP status codes you will meet most often, what each one means, and the first thing to… Beginner · Cheat sheet · Any system Article References · Status codes 15 Oct 2026
- 0037 Git cheat sheet The Git commands you reach for most, grouped by task and using the modern switch and restore forms. Copy, paste, and replace… Beginner · Cheat sheet · Any system Article Git 15 Oct 2026
- 0057 Shell cheat sheet: everyday commands A quick reference for moving around, managing files, viewing and searching text, checking processes and disk space in bash and zsh, with… Beginner · Cheat sheet · Linux, macOS Article Basics · Command-line tools 15 Oct 2026
- 0017 JavaScript array methods cheat sheet: map, filter, reduce and friends A quick reference for the array methods you use every day, with what each one returns and whether it changes the original… Beginner · Cheat sheet · Any system Article Basics 15 Oct 2026
- 0025 Regular expressions cheat sheet (JavaScript flavor) The regex syntax you actually use, from character classes and quantifiers to groups, lookarounds and flags, with the JavaScript methods that apply… Beginner · Cheat sheet · Any system Article Basics · Basics 15 Oct 2026
- 0002 Python cheat sheet: strings, lists, dicts and f-strings The everyday methods for text, lists and dictionaries, plus f-string formatting and comprehensions, each with a one-line example you can paste into… Beginner · Cheat sheet · Any system Article Basics 15 Oct 2026
- 0003 pathlib cheat sheet: files and folders in Python pathlib.Path is the modern way to build paths, read and write files, and list or search folders in Python. This page lists… Beginner · Cheat sheet · Any system Article Files & automation 15 Oct 2026